/** **
 * 依赖于天地图的D3.js支持库，以SVG的形式对车辆行驶位置及轨迹进行实时跟踪和动态展示。
 * 实现车辆沿路线运动，并有暂停等功能。
 * 注：chrome、safari、IE9及以上浏览器。
 * @author juyang
 * ****/

const T = window.T || {}

/**
 * 车辆的图片，包含坐标和旋转相关方法
 */
var CarOverlay = T.Overlay.extend({
  initialize: function(lnglat, options) {
    this.lnglat = lnglat
    this.setOptions(options)
    this.options = options
  },

  onAdd: function(map) {
    this.map = map
    var div = this.div = document.createElement('div')
    var img = this.img = document.createElement('img')
    div.style.position = 'absolute'
    div.style.width = this.options.width + 'px'
    div.style.height = this.options.height + 'px'
    div.style.marginLeft = -this.options.width / 2 + 'px'
    div.style.marginTop = -this.options.height / 2 + 'px'
    div.style.zIndex = 200// this._container.style.zIndex = zIndex;
    img.style.width = this.options.width + 'px'
    img.style.height = this.options.height + 'px'
    img.src = this.options.iconUrl
    div.appendChild(img)
    map.getPanes().overlayPane.appendChild(this.div)
    this.update(this.lnglat)
  },

  onRemove: function() {
    var parent = this.div.parentNode
    if (parent) {
      parent.removeChild(this.div)
      this.map = null
      this.div = null
    }
  },

  /**
   * 每个浏览器的偏转兼容
   * @returns {string}
   * @constructor
   */
  CSS_TRANSFORM: function() {
    var div = document.createElement('div')
    var props = [
      'transform',
      'WebkitTransform',
      'MozTransform',
      'OTransform',
      'msTransform'
    ]

    for (var i = 0; i < props.length; i++) {
      var prop = props[i]
      if (div.style[prop] !== undefined) {
        return prop
      }
    }
    return props[0]
  },

  /**
   * 偏转角度
   * @param rotate
   */
  setRotate: function(rotate) {
    this.img.style[this.CSS_TRANSFORM()] = 'rotate(' +
      rotate + 'deg)'
  },

  setLnglat: function(lnglat) {
    this.lnglat = lnglat
    this.update()
  },
  getLnglat: function() {
    return this.lnglat
  },
  setPos: function(pos) {
    this.lnglat = this.map.layerPointToLngLat(pos)
    this.update()
  },
  /**
   * 更新位置
   */
  update: function() {
    var pos = this.map.lngLatToLayerPoint(this.lnglat)
    this.div.style.left = pos.x + 'px'
    this.div.style.top = pos.y + 'px'
  }

})

T.CarOverlay = CarOverlay

T.CarTrack = function(map, opt) {
  this.map = map

  //  this.options = opt ? opt : {};
  //  this.options= this.setOptions(this.options,opt)
  // this.options.interval = this.options.interval ? this.options.interval : 1000;

  // this.options.uid = new Date().getTime();
  // this.uid = this.options.uid
  this.options.polylinestyle = this.setOptions(this.options.polylinestyle, opt.polylinestyle)
  this.options.carstyle = this.setOptions(this.options.carstyle, opt.carstyle)
  this.options = this.setOptions(this.options, opt)
  this.init()
}

T.CarTrack.prototype = {

  options: {

    interval: 1000,
    carstyle: {
      display: true,
      iconUrl: 'http://lbs.tianditu.gov.cn/images/openlibrary/car.png',
      width: 52,
      height: 26
    },
    polylinestyle: {
      display: true,
      color: 'red',
      width: '3',
      opacity: 0.8,
      lineStyle: ''
    }
  },

  init: function() {
    var datas = this.options.Datas
    this.options = this._deepCopy(this.options)
    this.options.uid = new Date().getTime()
    this.options.Datas = datas
    if (this.options.speed > 0) {
      var dis = this.distance(this.options.Datas)
      this.options.nodeslength = dis / this.options.speed// 总步数；
    } else {
      this.options.nodeslength = this.options.Datas.length// 总步数；
    }
    // 计步器
    this.options.Counter = 0
    // new出D3的图层，等待数据

    this.D3OverLayer = new T.D3Overlay(this.d3init, this.d3redraw, this.options)
    this.D3OverLayer.lineDatas = []// 线数据
    // 共享两个函数
    this.D3OverLayer.dataToLnglat = this.dataToLnglat
    this.D3OverLayer.applyLatLngToLayer = this.applyLatLngToLayer
    // this.D3OverLayer.updateSymbolLine = this.updateSymbolLine;
    // 接收，处理数据，加载轨迹和车辆；
    this.receiveData(this.map)
  },

  setOptions: function(obj, options) {
    for (var i in options) {
      if (i != 'polylinestyle' && i != 'carstyle') { obj[i] = options[i] }
    }
    return obj
  },
  /**
   *  清除所有元素，注销事件
   */
  clear: function() {
    this.state = 4
    this._Remove()
    delete this
  },

  _Remove: function() {
    this._pause()
    delete this._timer
    this._timer = null
    this.map.removeOverLay(this.carMarker)
    this.map.removeOverLay(this.D3OverLayer)
  },

  /** 处理传入的数据**/
  receiveData: function() {
    var opt = this.options
    var me = this

    if (opt.Datas instanceof Array && opt.Datas.length > 0) {
      // 绘制出D3渲染的线段；
      me.map.addOverLay(me.D3OverLayer)
      // 绘制车辆
      me.carMarker = new CarOverlay(me.dataToLnglat(this.options.Datas[0]), me.options.carstyle)
      if (!this.options.carstyle) { me.carMarker.hide() }
      me.map.addOverLay(this.carMarker)

      me.D3OverLayer.bringToBack()
    }
  },
  /**
   * 坐标获取
   * @param obj
   * @returns {T.LngLat}
   */
  dataToLnglat: function(obj) {
    if (obj instanceof T.LngLat || ('lat' in obj && 'lng' in obj)) { return obj } else {
      var coordinates = obj.geometry.coordinates
      var lnlat = new T.LngLat(coordinates[0], coordinates[1])
      return lnlat
    }
  },

  bind: function(fn, obj) {
    var slice = Array.prototype.slice
    if (fn.bind) {
      return fn.bind.apply(fn, slice.call(arguments, 1))
    }
  },

  /**
   * 坐标转换
   * @param d
   * @returns {*}
   */
  applyLatLngToLayer: function(d) {
    return this.map.lngLatToLayerPoint(this.dataToLnglat(d))
  },

  d3init: function(sel, transform) {
    sel.append('path')
      .attr('id', 'polyline' + this.options.uid)
      .attr('fill', 'none')
      .attr('stroke', this.options.polylinestyle.color)
      .attr('width', this.options.polylinestyle.width)
      .attr('opacity', this.options.polylinestyle.opacity)
      .attr('display', this.options.polylinestyle.display ? 'block' : 'none')

    sel.append('path')
      .attr('id', 'dynamicLine' + this.options.uid)
      .attr('fill', 'none')
      .attr('stroke', this.options.polylinestyle.color)
      .attr('width', this.options.polylinestyle.width)
      .attr('opacity', this.options.polylinestyle.opacity)
      .attr('display', this.options.dynamicLine && this.options.polylinestyle.display ? 'block' : 'none')
  },

  d3redraw: function() {
    // 像素点坐标转字符串
    function pointsToPath(rings, closed) {
      var str = ''
      var i; var j; var len; var len2; var points; var p

      for (i = 0, len = rings.length; i < len; i++) {
        points = rings[i]

        for (j = 0, len2 = points.length; j < len2; j++) {
          p = points[j]
          str += (j ? 'L' : 'M') + p.x + ' ' + p.y
        }

        // closes the ring for polygons; "x" is VML syntax
        str += closed ? (L.Browser.svg ? 'z' : 'x') : ''
      }

      // SVG complains about empty path strings
      return str || 'M0 0'
    }

    function lnglatsTopoints(map, lnglats) {
      var pts = []
      for (var k = 0; k < lnglats.length; k++) {
        pts.push(map.lngLatToLayerPoint(lnglats[k]))
      }
      return pts
    }
    var datasStr1 = pointsToPath([lnglatsTopoints(this.map, this.options.Datas)], false)// this._svg.
    var lineDatas = this.lineDatas ? this.lineDatas : this.D3OverLayer.lineDatas
    var datasStr2 = pointsToPath([lnglatsTopoints(this.map, lineDatas)], false)// this.options.dynamicLine ? this.lineDatas : this.options.Datas;
    // 线数据的重新计算分两种情况 1、缩放地图时要重新计算容器坐标 2、动态线的时候要重绘线
    d3.select('path#polyline' + this.options.uid).attr('d', datasStr1)
      .attr('stroke-width', this.options.polylinestyle.width + 'px')

    d3.select('path#dynamicLine' + this.options.uid).attr('d', datasStr2)
      .attr('stroke-width', this.options.polylinestyle.width + 'px')
  },

  /**
   * 随着时间
   */
  update: function() {
    // 计步器+1
    this.options.Counter++
    var linePath = d3.select('path#polyline' + this.options.uid)
      .attr('display', this.options.polylinestyle.display && !this.options.dynamicLine
        ? 'block' : 'none')
    // 轨迹像素长度
    var nodeslength = (this.options.speed > 0
      ? Math.ceil(this.options.nodeslength) + 1
      : Math.ceil(this.options.nodeslength)
    )

    if (this.options.speed > 0) {
      // 计算小车所在的像素点
      var l = linePath.node().getTotalLength()
      var s = (this.options.Counter - 1) / this.options.nodeslength
      var l1 = s * l
      var p1 = linePath.node().getPointAtLength(l1)
      this.D3OverLayer.lineDatas = []
      if (this.options.Datas[0]) { this.D3OverLayer.lineDatas.push(this.options.Datas[0]) }
      var lsum = 0
      // 计算像素点前的所有包含的轨迹坐标的像素点
      for (var k = 0; k < this.options.Datas.length - 1; k++) {
        var p2 = this.map.lngLatToLayerPoint(this.options.Datas[k])
        var p3 = this.map.lngLatToLayerPoint(this.options.Datas[k + 1])
        var l2 = p2.distanceTo(p3)
        lsum = lsum + l2
        if (l1 > lsum) { this.D3OverLayer.lineDatas.push(this.options.Datas[k + 1]) } else {
          break
        }
      }
      if (this.options.Counter < nodeslength) {
        var lnglat = this.map.layerPointToLngLat(p1)
        this.D3OverLayer.lineDatas.push(lnglat)
      }
    } else {
      this.D3OverLayer.lineDatas = this.options.Datas.slice(0, this.options.Counter)
    }

    this.carMarker.setLnglat(this.D3OverLayer.lineDatas[this.D3OverLayer.lineDatas.length - 1])
    // 车辆偏转角计算。
    if (this.options.Counter > 1) {
      var rotate = this.angle(
        this.D3OverLayer.lineDatas[this.D3OverLayer.lineDatas.length - 2],
        this.D3OverLayer.lineDatas[this.D3OverLayer.lineDatas.length - 1])
      this.carMarker.setRotate(rotate)
    } else {
      this.carMarker.setRotate(0)
    }
    if (this.options.dynamicLine) this.d3redraw()

    /** 回调函数，车辆每移动一次触发的函数
     *Lnglat：经过的坐标
     *index：节点序号。
     *length:总节点数量。
     ***/
    if (this.options.passOneNode) {
      this.options.passOneNode(
        this.carMarker.getLnglat(),
        this.options.Counter,
        nodeslength
      )
    }
    if (this.options.Counter >= nodeslength) {
      this.options.Counter = 0
    }
  },

  /**
   * 计算轨迹的距离
   * @returns {number}
   */
  distance: function() {
    var d = 0
    var datas = this.options.Datas
    var l = datas.length
    for (var i = 0; i < l - 1; i++) {
      var p1 = this.dataToLnglat(datas[i])
      var p2 = this.dataToLnglat(datas[i + 1])
      d = d + this.map.getDistance(p1, p2)
    }
    return d
  },

  /**
   *在每个点的真实步骤中设置小车转动的角度
   */

  angle: function(curPos, targetPos) {
    var deg = 0
    if (targetPos.lng != curPos.lng) {
      var tan = (targetPos.lat - curPos.lat) / (targetPos.lng - curPos.lng)
      var atan = Math.atan(tan)
      deg = -atan * 360 / (2 * Math.PI)
      if (targetPos.lng < curPos.lng) {
        deg = -deg + 90 + 90
      } else {
        deg = -deg
      }
      return -deg
    } else {
      var disy = targetPos.lat - curPos.lat
      var bias = 0
      if (disy > 0) { bias = -1 } else { bias = 1 }
      return (-bias * 90)
    }
    return
  },

  /**
   *开始运动
   */
  start: function() {
    if (this.state == 4) return
    this.state = 1
    if (this.D3OverLayer && !this._timer) {
      this._timer = setInterval(this.bind(this.update, this),
        this.options.interval)
    }
  },

  /**
   * 停止运动
   */
  stop: function() {
    if (this.state == 4) return
    this.state = 2
    this._pause()
    this._Remove()
    this.init()
  },

  _pause: function() {
    if (this._timer) {
      clearTimeout(this._timer)
      delete this._timer
      this._timer = null
    }

    return this
  },
  /**
   * 暂停运动
   */
  pause: function() {
    if (this.state == 4) return
    this.state = 3
    this._pause()
  },
  _deepCopy: function(source) {
    var result = {}
    for (var key in source) {
      result[key] = typeof source[key] === 'object' ? this._deepCopy(source[key]) : source[key]
    }
    return result
  }

}

